We discuss exclusive $\phi$-meson electroproduction off the proton near threshold within the GPD factorization framework.
We propose the "threshold approximation" in which only the leading term of the
conformal partial wave expansion of the process amplitudes
is kept in both the quark and gluon exchange channels.
We test the validity of this approximation to next-to-leading order in QCD...
Azimuthal modulations are crucial in the phenomenological extraction and separation of various generalized parton distributions (GPDs). Traditionally, GPDs could be extracted from angular modulations of the deeply virtual Compton scattering (DVCS) in the Breit frame. However, the Bethe-Heitler subprocess (BH) interferes with the DVCS and contaminates the azimuthal modulations from DVCS, making...
Hadron matrix elements of the QCD energy-momentum tensor are expressed by the gravitational form factors. The gravitational form factors are related to a particular moment of the GPDs, and are relevant to EIC physics. The forward (zero momentum transfer) values of the gravitational form factors allow for a decomposition of the hadron mass into the contributions from quarks and gluons, and the...
Unveiling chiral-odd dimeson generalized distribution amplitudes
S. Bhattacharya, R. Boussarie, B. Pire, L. Szymanowski
Chiral-odd generalized distribution amplitudes which are the crossed matrix elements from chiral-odd quark GPDs in a meson contain valuable information on the transversity (or tensor) structure of mesons.
They are up to now inaccessible to experimental investigation. We...
